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Method of hot working a screwed drill pipe joint

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Publication number
US2761205A
US2761205A US31995952A US2761205A US 2761205 A US2761205 A US 2761205A US 31995952 A US31995952 A US 31995952A US 2761205 A US2761205 A US 2761205A
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Grant
Patent type
Prior art keywords
pipe
drill
threadless
joint
tool
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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Inventor
Siklosi Johann
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
FA SCHOELLER-BLECKMANN STAHLWERKE AG
SCHOELLER BLECKMANN STAHLWERKE
Original Assignee
SCHOELLER BLECKMANN STAHLWERKE
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Publication date
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16LPIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L15/00Screw-threaded joints; Forms of screw-threads for such joints
    • F16L15/001Screw-threaded joints; Forms of screw-threads for such joints with conical threads
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21DWORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D39/00Application of procedures in order to connect objects or parts, e.g. coating with sheet metal otherwise than by plating; Tube expanders
    • B21D39/04Application of procedures in order to connect objects or parts, e.g. coating with sheet metal otherwise than by plating; Tube expanders of tubes with tubes; of tubes with rods
    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21BEARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B17/00Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods ; Cables; Casings; Tubings
    • E21B17/02Couplings; joints
    • E21B17/04Couplings; joints between rod or the like and bit or between rod and rod or the like
    • E21B17/042Couplings; joints between rod or the like and bit or between rod and rod or the like threaded
    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21BEARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B17/00Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods ; Cables; Casings; Tubings
    • E21B17/02Couplings; joints
    • E21B17/04Couplings; joints between rod or the like and bit or between rod and rod or the like
    • E21B17/042Couplings; joints between rod or the like and bit or between rod and rod or the like threaded
    • E21B17/043Couplings; joints between rod or the like and bit or between rod and rod or the like threaded with locking means
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16LPIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L15/00Screw-threaded joints; Forms of screw-threads for such joints
    • F16L15/001Screw-threaded joints; Forms of screw-threads for such joints with conical threads
    • F16L15/004Screw-threaded joints; Forms of screw-threads for such joints with conical threads with axial sealings having at least one plastically deformable sealing surface
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S285/00Pipe joints or couplings
    • Y10S285/916Molecular change
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49826Assembling or joining
    • Y10T29/49863Assembling or joining with prestressing of part
    • Y10T29/49865Assembling or joining with prestressing of part by temperature differential [e.g., shrink fit]
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49826Assembling or joining
    • Y10T29/49908Joining by deforming
    • Y10T29/49925Inward deformation of aperture or hollow body wall
    • Y10T29/49927Hollow body is axially joined cup or tube
    • Y10T29/49929Joined to rod

Description

United States Patent C) lVIETHOD OF HOT WORKING A SCREWED DRILL PIPE JOINT Johann Siklosi, Vienna, Austria, assignor to Fa. Schoeller- Bleckmann Stahlwerke Aktiengesellschaft, Vienna, Austria Application November 1-2, 1952, Serial No. 319,959 Claims priority, application Austria September 23,1952

1 Claim. (Cl. 29-447) 'lilris invention relates to pipe assemblies and more particularly to a method of hot working drill pipes screwed to a tool joint.

The standardized thread used to connect the drill pipe and tool joint has the disadvantage that higher stresses effective at the runouts of the thread of the drill pipe lead to fatigue failure. To eliminate this risk and to achieve a more intimate connection of the drill pipe with the tool joint, it has been proposed to shrink the thread and the threadless lap of the tool joint on the mating thread and the threadless sealing surface of the drill pipe, at about 350 deg. C. A disadvantage of this type of assembly, in which the thread and the threadless lap of the tool joint must be designed with corresponding shrinkage allowances, resides in the very close tolerances for the diameters of the threads and of the threadless sealing surfaces of the tool joint and of the drill pipe. Moreover, the temperature rise of the thread of the tool joint has the disadvantage that it causes a change of the lead thereof as compared with the theoretical value and as a result that thread must be screwed with an incorrect lead on a drill pipe thread having a theoretically correct lead,

It is an object of the present invention to provide perfect sealing surfaces and a safety zone for the runouts of the thread, while maintaining the taper, and the flank diameter and thread profile of API standard threads and avoiding,r a temperature rise of the thread of the tool joint.

In the process according to the invention, this object is achieved in that a tight fit is produced between the threadless sealing surfaces of the tool joint and the drill pipe, and if desired also between the threads of the tool joint and the drill pipe, by a hot-working treatment consisting of expanding by means of rolls or a mandrel, pressing, forging or drawing, and performed after these two parts have been screwed together.

Thus it is a feature of the invention to provide in the process for the construction of pipe assemblies by screwing a fitting having a thread extending inwardly from a point spaced from one end of the fitting, on a correspondingly threaded pipe to cause a threadless sealing surface extending on said fitting between said end and said thread to lie adjacent to a threadless sealing surface of said pipe, the step of forcing said sealing surfaces together as a tight fit by a deforming treatment in hot condition effected after said fitting has thus been screwed on said pipe.

It is another feature of the invention to provide a pipe assembly which comprises a pipe fitting having a thread extending inwardly from a point spaced from one end of the fitting, and a correspondingly threaded pipe having said fitting screwed thereto, said fitting and said pipe having each a portion carrying a threadless sealing surface, said sealing surfaces tightly fitting each other, at least one of said portion being deformed in hot condition.

The two parts may be forced against each other e. g.,

2,761,205 Patented Sept. 4 1956 byexpanding the screwed drill pipe endparticularly its threadless sealingjface, in diameter, preferably by means of rolls or a mandrel, to force the threadless `sealing surface of the drill pipe to the threadless sealing surface of the tool joint.

In another embodiment of the process the parts to be connected are forced together into tight contact, by pressing, hammering, or drawing through a drawing die, the threadless lap of the tool joint, preferably in a hot state, on'the threadless sealing surface of the drill pipe, after these parts 'have been screwed together.

To explain the process and the resulting assembly the drawing shows in Fig. l` an embodiment of a drill pipe assembly in longitudinal section, and-in Fig; 2 a cross sectional view `taken along line 2 2 of Fig. l.

According to Fig. l the tool joint 1 comprising the thread 2, the tubular end portion 3, and a threadless sealing surface 4, is screwed to the drill pipe 5 having a thread 6. Previously the lap 3 of the tool joint l was provided only to protect the runout of the thread and had no fixed connection to the drill pipe. According to the invention the drill pipe end 8, particularly the threadless sealing surface 7 of the drill pipe 5 and, if desired, also the thread 6 of the drill pipe 5, are expanded by rolling, e. g., on an automatic pipe caulking machine, or by means of a mandrel, to force them tightly against the threadless sealing surface 4 and the thread 2, respectively, of the tool joint and thus to obtain a tight fit between the lap 3 and the drill pipe 5. By this expanding step the physical properties of the pipe steel are influenced very favorably and all fits are achieved much more uniformly than by the known shrinking step.

Very tight and uniform fits are achieved by forcing the threadless tubular end portion 3 of the tool joint, in a heated state, on the threadless sealing surface 7 of the drill pipe 5, e. g., by pressing or by forging it thereon with a suitable forging device, or drawing it thereon through a drawing die. The threadless lap 3 is to be heated, if possible locally, to, e. g., about 850 deg. C., preferably by electric induction and, if necessary, while the adjacent thread 2 of the tool joint is cooled.

This tight fit of the threadless sealing surfaces can be improved to resist even torsional stress by roughing one of the sealing surfaces and forcing it tightly on the other sealing surface, which was previously heated. This may be accomplished, el g., by roughing the threadless sealing surface 7 of the drill pipe 5 by milling them, locally heating the threadless lap 3 of the tool joint 1 to about 850 deg. C. after it has been screwed on the pipe, and pressing, or forging in a suitable die, the heated lap of the tool joint 3 on the drill pipe, or drawing it thereon through a drawing die.

By expanding the drill pipe by means of rolls or mandrel the theoretical diameter of the thread 6 of lthe drill pipe is influenced only to a tolerable extent, which has no detrimental effects in practice, whereas it is not altered at all by the step of pressing, forging, or drawing the threadless lap 3 of the tool joint thereon.

The threadless sealing surfaces 4 and 7 of the tool joint and of the drill pipe being forced against each other, they need not be turned bright.

When the threadless lap 3 of the tool joint is pressed, hammered, or drawn on the drill pipe 5, the threadless sealing surface 4 of the tool joint may be of a diameter larger than the threadless sealing surface 7 of the drill pipe, because it will be given a tight fit on the drill pipe in any case by the subsequent pressing.

I claim:

A method for attaching a drill pipe having an end portion formed with an outer thread and an annular threadless outer surface adjalcent the outer thread to a steel tool joint formed with an inner thread and having a tubular end portion having an annular inner surface adjacent said inner thread, comprising the steps of screwing said tool joint over said drill pipe into a position in which said annular inner surface of said tubular end portion of said tool joint is located opposite and surrounding said annular threadless outer surface of said drill pipe; thereupon heating said tubular end portion of said tool joint; and mechanically deforrning and pressing said heated tubular end portion of said tool joint in hot condition against said annular threadless outer surface to reduce the diameter of said inner annular surface whereby the same engages in a tight t said outer threadless annular surface of said drill pipe.

References Cited in the le of this patent UNITED STATES PATENTS 105,290 Allison July 12, 1870 4 Kearney Aug. 10, 1909 Davis June 30, 1914 Washburne Mar. 8, 1927 Deckard Nov. 12, 1929 Loffler Nov. 19, 1929 Eaton Aug. 4, 1931 Protin Jan. 9, 1934 Childs Sept. 15, 1936 Fletcher May 30, 1939 Osmun May 28, 1940 Boynton Mar. 18, 1941 Castellanos May 26, 1942 Boynton May 11, 1943 Priebe Nov, 28, 1944 Conroy May 7, 1946 Edelmann Nov. 18, 1947 Brace Feb. 17, 1953 Grin Apr. 28, 1953

US2761205A 1952-09-23 1952-11-12 Method of hot working a screwed drill pipe joint Expired - Lifetime US2761205A (en)

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Application Number Priority Date Filing Date Title
AT184039T 1952-09-23

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US (1) US2761205A (en)
DE (1) DE951712C (en)
FR (1) FR1083083A (en)
GB (1) GB740726A (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3193918A (en) * 1962-01-08 1965-07-13 Russell C Heldenbrand Method of fabricating drill pipe
DE1218378B (en) * 1963-12-20 1966-06-08 Reed Roller Bit Co Threaded connection, in particular for drill collars
US4356612A (en) * 1980-03-31 1982-11-02 Cameron Iron Works, Inc. Method of producing a forged product
FR2541604A1 (en) * 1983-02-25 1984-08-31 Skf Cie Applic Mecanique connecting rod manufacturing process has restricted entry ends and rods obtained by this method
US4538339A (en) * 1981-09-02 1985-09-03 National Set Screw Method of making a sucker rod assembly
US20040148758A1 (en) * 2001-05-24 2004-08-05 Lohbeck Wilhelmus Christianus Maria Radially expandable tubular with supported end portion
US20060260802A1 (en) * 2003-05-05 2006-11-23 Filippov Andrei G Expansion device for expanding a pipe
US20080231042A1 (en) * 2007-03-22 2008-09-25 Semyon Brayman Method for joining ends of sections of pipe

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1062649B (en) * 1955-04-12 1959-08-06 Fuchs Fa Otto OElfoerderungsanlage for deep drilling
FR1287022A (en) * 1960-05-16 1962-03-09 Reynolds Metals Co Improvements to tube fittings, particularly for drill tubes
US4588213A (en) * 1983-10-05 1986-05-13 Thread Technology International, Inc. Threaded pipe connection

Citations (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US105290A (en) * 1870-07-12 Improvement in pipe-couplings
US930863A (en) * 1907-12-09 1909-08-10 Thomas Albert Kearney Process for banding projectiles.
US1101729A (en) * 1913-11-24 1914-06-30 Standard Underground Cable Co Compound metallic article.
US1619901A (en) * 1922-02-23 1927-03-08 Oliver Typewriter Co Method of making two-piece valves
US1735563A (en) * 1928-05-25 1929-11-12 Charles L Deckard Method of securing metal end couplings on tubular members
US1736610A (en) * 1924-04-11 1929-11-19 Loffler Stephan Method of manufacturing high-pressure boilers
US1817808A (en) * 1930-11-20 1931-08-04 Spang Chalfant & Company Inc Method of making tight threaded joints
US1942518A (en) * 1933-06-22 1934-01-09 Pittsburgh Steel Co Pipe joint
US2054118A (en) * 1935-06-11 1936-09-15 Reed Roller Bit Co Tool joint and method of making same
US2160263A (en) * 1937-03-18 1939-05-30 Hughes Tool Co Pipe joint and method of making same
US2202261A (en) * 1937-08-23 1940-05-28 Fred N Osmun Safety joint
US2234957A (en) * 1938-10-28 1941-03-18 Boynton Alexander Thread locking means
US2284260A (en) * 1940-11-15 1942-05-26 Hughes Tool Co Method of making sealing supports for tool joints
US2318590A (en) * 1938-11-28 1943-05-11 Boynton Alexander Thread lock
US2363990A (en) * 1941-08-22 1944-11-28 Smith Corp A O Method of preparing and welding metal parts
US2399790A (en) * 1943-05-27 1946-05-07 Walter Fritsch Method of permanently attaching hose couplings
US2430921A (en) * 1943-07-03 1947-11-18 Edelmann Leo Method of making hose couplings
US2628516A (en) * 1949-07-09 1953-02-17 Westinghouse Electric Corp Tube making process
US2636753A (en) * 1948-04-19 1953-04-28 Claude L Griffin Tool joint-pipe connection

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US284260A (en) * 1883-09-04 Chables w
US1438751A (en) * 1918-07-06 1922-12-12 Isles Leonard H Des Conduit for thermotemperature circuits of grain tanks
US2001204A (en) * 1934-03-03 1935-05-14 James A Long Pipe joint and method of making the same

Patent Citations (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US105290A (en) * 1870-07-12 Improvement in pipe-couplings
US930863A (en) * 1907-12-09 1909-08-10 Thomas Albert Kearney Process for banding projectiles.
US1101729A (en) * 1913-11-24 1914-06-30 Standard Underground Cable Co Compound metallic article.
US1619901A (en) * 1922-02-23 1927-03-08 Oliver Typewriter Co Method of making two-piece valves
US1736610A (en) * 1924-04-11 1929-11-19 Loffler Stephan Method of manufacturing high-pressure boilers
US1735563A (en) * 1928-05-25 1929-11-12 Charles L Deckard Method of securing metal end couplings on tubular members
US1817808A (en) * 1930-11-20 1931-08-04 Spang Chalfant & Company Inc Method of making tight threaded joints
US1942518A (en) * 1933-06-22 1934-01-09 Pittsburgh Steel Co Pipe joint
US2054118A (en) * 1935-06-11 1936-09-15 Reed Roller Bit Co Tool joint and method of making same
US2160263A (en) * 1937-03-18 1939-05-30 Hughes Tool Co Pipe joint and method of making same
US2202261A (en) * 1937-08-23 1940-05-28 Fred N Osmun Safety joint
US2234957A (en) * 1938-10-28 1941-03-18 Boynton Alexander Thread locking means
US2318590A (en) * 1938-11-28 1943-05-11 Boynton Alexander Thread lock
US2284260A (en) * 1940-11-15 1942-05-26 Hughes Tool Co Method of making sealing supports for tool joints
US2363990A (en) * 1941-08-22 1944-11-28 Smith Corp A O Method of preparing and welding metal parts
US2399790A (en) * 1943-05-27 1946-05-07 Walter Fritsch Method of permanently attaching hose couplings
US2430921A (en) * 1943-07-03 1947-11-18 Edelmann Leo Method of making hose couplings
US2636753A (en) * 1948-04-19 1953-04-28 Claude L Griffin Tool joint-pipe connection
US2628516A (en) * 1949-07-09 1953-02-17 Westinghouse Electric Corp Tube making process

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3193918A (en) * 1962-01-08 1965-07-13 Russell C Heldenbrand Method of fabricating drill pipe
DE1218378B (en) * 1963-12-20 1966-06-08 Reed Roller Bit Co Threaded connection, in particular for drill collars
US4356612A (en) * 1980-03-31 1982-11-02 Cameron Iron Works, Inc. Method of producing a forged product
US4538339A (en) * 1981-09-02 1985-09-03 National Set Screw Method of making a sucker rod assembly
FR2541604A1 (en) * 1983-02-25 1984-08-31 Skf Cie Applic Mecanique connecting rod manufacturing process has restricted entry ends and rods obtained by this method
EP0120735A1 (en) * 1983-02-25 1984-10-03 SKF COMPAGNIE D'APPLICATIONS MECANIQUES & CIE. S.N.C. Method for the production of tubular rods with necked ends, and tubular rods made by this method
US20040148758A1 (en) * 2001-05-24 2004-08-05 Lohbeck Wilhelmus Christianus Maria Radially expandable tubular with supported end portion
US7040018B2 (en) * 2001-05-24 2006-05-09 Shell Oil Company Radially expandable tubular with supported end portion
US20060260802A1 (en) * 2003-05-05 2006-11-23 Filippov Andrei G Expansion device for expanding a pipe
US7597140B2 (en) 2003-05-05 2009-10-06 Shell Oil Company Expansion device for expanding a pipe
US20080231042A1 (en) * 2007-03-22 2008-09-25 Semyon Brayman Method for joining ends of sections of pipe
US7918006B2 (en) * 2007-03-22 2011-04-05 Semyon Brayman Method for joining ends of sections of pipe

Also Published As

Publication number Publication date Type
FR1083083A (en) 1955-01-05 grant
GB740726A (en) 1955-11-16 application
DE951712C (en) 1956-10-31 grant

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